Asking as I donβt know which counterpowers could prevent this at state level for instance
He possibly can, but this will basically only affect federal paperwork: The Census, IRS, military enlistment, and so on. It doesnβt mean ungendered restrooms are going away, and it doesnβt affect the states.
Itβs bluster and insult, the things he does best.
Passports. A lot of folks might have to get new passports if their old ones are rendered invalid because of the gender marker.
Tbh, I never fixed mine (to X) because that felt like increasing my risk while traveling, when I can stealth as my assigned gender while on travel/outside my comfort zone.